St. Vladimir, also known as Vladimir the Great, was a ruler of Kievan Rus' from 980 to 1015. He is best known for his role in the Christianization of the region, converting to Christianity and promoting it as the state religion. His reign marked a significant cultural and religious shift, leading to the establishment of Orthodox Christianity in Eastern Europe. Vladimir is often celebrated as a saint in the Eastern Orthodox Church, recognized for his contributions to the faith and the unification of the Slavic peoples. His legacy includes the founding of churches and the promotion of literacy and education, which helped shape the cultural landscape of Ukraine and Russia.